Nick Brown needs to plan work on 4 jobs that are listed in the table to the right. Two jobs, A and B, are already available (morning of day 0). Nick knows that two other jobs, C and D, will be available in the morning 4 days from today. Each job has to be completed by the morning of its due day. Once Nick starts working on a given job, he has to finish it before starting another job.

Job ID	Processing Time (days)	Arrival Day	Due Day
A	5	0	25
B	3	0	15
C	7	4	12
D	8	4	22

1. Assuming that jobs are ordered A-B-C-D, calculate:

   1. Average job completion time

   2. Average job flow time

   3. Average number of jobs in the system

   4. Average job lateness

2. Nick does not like to have too many jobs at his desk and is considering using the SPT rule.

   1. What is the new order of jobs by SPT?

   2. With the new order, did the average number of jobs in the system decrease? Justify your answer.

3. Nick is worried that some jobs are late.

   1. How should the jobs be scheduled to minimize the average lateness? Draw a Gantt

      chart presenting suggested schedule.

   2. What is the new average job lateness?